Slide closures of this type are well known to be used in continuous casting lines for opening and closing the spout opening of a metallurgical vessel. During operation the molten steel gives rise to high temperatures that are also transferred to the slider housing in the area surrounding the fireproof slider plates. In contrast, in the outer region of the housing substantially lower temperatures prevail, for example close to ambient temperature in the surrounding area. Nevertheless, the slider housing must also be stable in this region for the fastening of the holding means for the slider unit.
A slide closure of the type specified at the start is disclosed in publication EP-A-1 119 428 in which the housing part extends over the entire length and sideways to outside of the holding means in the direction of displacement so that these holding means are positioned in the region between the slider plates and the longitudinal walls of the housing part. In this way high rigidity of the slider housing can be achieved, but at the same time increased susceptibility to cracking occurs here because the large drop in temperature between the inside and the outside region of the housing causes different heat expansions and so very high stresses in the transition zone between the two regions.
In addition, the holding means fastened within the housing part on both sides of the closure plates are respectively connected to one another by means of a connection rod. The effect of this is that the slider unit can then only be released from the housing part if it can be displaced into this position lying outside of the open and the closed position in which tension of the spring components is then released.